Surface‐emitting semiconductor lasers have attracted attention because of their applications in new fields of optoelectronics such as parallel processing, optical interconnections, etc. In these lasers, light is emitted perpendicularly to the semiconductor substrate which creates the possibility of two‐dimensional parallel integration.
In this paper, the state of research on surfaceemitting semiconductor lasers is discussed first as are various structures of surface‐emitting semiconductor lasers with vertical, horizontal, and folded resonators. The formation of a buried structure or highly reflective configuration employed to achieve the low threshold operation of surface‐emitting semiconductor lasers with vertical cavities are focused upon and their oscillation characteristics of two‐dimensional array arrangements are introduced.
Finally, the recent progress of surface‐emitting lasers and surface‐operating functional devices together with their future prospects are presented.